Guiding light in materials with a low refractive index such as air is thought to be prohibited in conventional waveguides, which are based on total internal reflection (TIR). High optical intensity is of foremost importance in many fields of science and technology, due to the innumerous relevant physical phenomena thereby attained, and their immediate applications in sensing, modulation, switching, etc. There is a great scientific and technological interest in achieving high optical intensity in a very small cross-section or volume of matter in order to enable low power integrated devices. Methods and devices providing high optical intensity in a very small cross-section or volume of matter should easily connect with and be compatible with known integrated circuit technologies.